Pyrotechnic radiator construction

ABSTRACT

A pyrotechnic radiator comprises a radiation-emitting body and an energy source heating it. The radiator is particularly adapted for use in locating moving bodies such as guided missiles using infrared equipment. The radiation-emitting body comprises a thinwalled tube which is formed by bending into the desired geometry for locating it in a receiver. The energy source comprises a pyrotechnic incandescent composition which gives off heat energy without an appreciable evolution of gas. The receiver for the radiation-emitting body is constructed so that oxygen necessary for the optimum radiation yield can be fed to the radiator in dosed amounts. For this purpose, the receiver includes a plurality of individual slots which are distributed around at least one surface of the exterior and which provides a communication from the exterior to the interior of the receiver.

United States Patent 1 1 3,695,180

Stetter et al. 51 Oct. 3, 1972 PYROTECHNIC RADIATOR Primary ExaminerBanjamin A. Borchelt CONSTRUCTION Assistant Examiner-H. J. Tudor [72] Inventors: Gunter Stetter; Ullrich Reinemann, Att0mey McGlew and Tore both of Munich, Germany ABSTRACT [73] Assignee: Messerschmitt-BoIkow-Blohm Gesellschafl m beschranktel. Hub A pyrotechmc radlator comprises a radiation-emitting mg, Munich Germany body and an energy source heating it. The radiator is particularly adapted for use in locating moving bodies Fledi 1970 such as guided missiles using infrared equipment. The 2 1 App]. 88,441 radiation-emitting body comprises a thin-walled tube which is formed by bending into the desired geometry [30] Pol-fig Applicatlo Pnomy Data for locating it in a receiver. The energy source com- 1969 Germany 19 57 524-7 prises a pyrotechnic incandescent composition which 52 US. Cl. ..102/87, 102/375, 102/66 gives eff heat gy without an appreciable evolution 51 1111.01. ..F42b 11/16, F42b 13/34 of gee The receiver for the radiation-emitting y is [58] Field of Search ..102/37.5, 37.8, 87, 66, 90, Constructed o that oxygen necessary for the optimum 102/6 radiation yield can be fed to the radiator in dosed amounts. For this purpose, the receiver includes a plu- [56] References Cited rality of individual slots which are distributed around at least one surface of the exterior and which provides UNITED STATES PATENTS a communication from the exterior to the interior of 2,986,999 6/1961 Fiedler et a] 102/87 the recever- 3,399,621 9/1968 Schillreff ..102/37.8 3,354,828 1 1/1967 Shefler et al ..102/37.s 4 Dmwmg F'gum i L 25' f l 7:.

PATENTEU B 3 I97? INVENTORS Gunter Stetter Ullrich Reinemunn y M/Zm WC; ATTORNEYS PYROTECI-INIC RADIATOR CONSTRUCTION SUMMARY OF THE INVENTION This invention relates in general to the construction of a pyrotechnic radiator and in particular to a pyrotechnic radiator which includes a tubular radiator having a pyrotechnic substance therein which is located within a receiver and has means for supplying dosed quantities of oxygen to the interior of the receiver for controlling the optimum radiation yield.

The present invention is an improvement over the invention disclosed and described in US. Pat. Application Ser. No. 844,797 filed July 25, 1969, particularly in respect to the radiation emitter package including the receiver and the radiation emitter itself which is constructed to provide an optimum means for feeding the necessary oxygen for the radiation emitter operation. The invention is particularly directed to radiation emitters comprising a thin-walled tube of any cross-section which is formed by bending it to the desired geometry of its receiver. The energy source is a pyrotechnic incandescent composition which fills the tube and gives off its heat energy without an appreciable evolution of gas. Such radiators, which are independent of external energy sources, are used preferably in connection with the operation of automatic moving bodies and their function is to make the bodies carrying them visible for an infrared position finder working in their spectral region or for an observer. Since the pyrotechnic substance is introduced into the tube before it is bent, such radiators can be produced continuously in a simple manner and be bent subsequently to any configuration. The manufacturing costs of such radiators are thus considerably reduced. In addition, optical filters for the spectral limitation of the radiation and/or diaphragms for the modulation of the emitted radiation can be arranged in a simple manner in the immediate proximity of the radiation-emitting body.

It was found in practical tests with such radiators, particularly those which are arranged in a chamber which is sealed from the outside because of the optical filters or diaphragms, that the intensity of the emitted radiation is not quite satisfactory. Extensive investigations of the chemical and physical relationships and the reaction occurring during the combustion of these radiators have shown that this loss of intensity is due primarily to a lack of oxygen supplied to the radiator proper, that is, to the outer surface of the tube containing the incandescent composition. It was found that the thin-walled tube which emits the radiation after it has been heated by the incandescent composition gives off a particularly intensive radiation whenever the tube, which consists mostly of metal, is transformed into an oxide or provided with an oxide film before or during the combustion of the pyrotechnic incandescent composition.

Since the radiation tube containing the pyrotechnic incandescent composition must be a very thin-walled construction to permit rapid heating of the tube and also to permit a very low weight of the radiator and a simple manufacture in view of the bending characteristics, a metal oxide is not suitable as a material for the tube because it obviously does not have the necessary strength. For this reason, the oxidation of the thinwalled tube which is necessary to increase the intensity of the radiator, can be effected only during the combustion of the pyrotechnic incandescent composition. However, there is not enough oxygen available for such oxidation if the radiator is arranged in a chamber which is closed, for example, by optical filters or diaphragms, because the oxygen enclosed in such a chamber is insufficient for the formation of the necessary oxide film. ln open radiators which are connected with a highspeed missile, the amount of oxygen arriving at the pyrotechnic substance is so great that the radiator is destroyed by excessive oxidation, that is, combustion.

In accordance with the invention, the pyrotechnic radiator package is improved, so that an optimum output of the radiator is achieved when the radiator is sealed off from the external air supply because of the use of optical filters or diaphragms and also when there is an open radiator connected with a high-speed missile so that an oversupply of oxygen is not received. The invention provides a receiver in combination with the radiator designed so that optimum amounts of oxygen necessary for radiation yield can be supplied to the pyrotechnic radiator. The receiver is constructed with at least one outer wall having individual slots which are distributed over at least one surface of the receiver and which provide means for admitting air in a turbulent flow and in dosed quantities to the interior of the receiver and to the emitter. In the preferred arrangement of the slots, a much higher radiation output can be achieved than was possible heretofore with radiators which are not sealed off from the outside air, and radiators which have a connection to the outside air but which do not receive an artificially increased oxygen supply. This phenomenon can be utilized with particular advantage, for example, in missiles by supplying the radiator with an exactly dosed quantity of oxygen through the certain arrangement of the slots selected in dependence on the missile speed in order to effect a uniform oxidation of the thin tube containing the pyrotechnic incandescent compositionand such dosing of oxygen will be sufiicient for optimum radiation yield. If too little oxygen is supplied to the tube, the tube is not sufliciently oxidized so that no optimum radiation intensity can be achieved. If too much oxygen is supplied, on. the other hand, the tube is oxidized to such an extent that it burns through after a short time. By the controlled oxidation of the tube material, in accordance with the invention, an additional exothermic reaction takes place, presumably in addition to the production of energy in the normal reaction of the pyrotechnic substance. This effects a considerable increase of the radiation intensity. With correct dosing of the oxygen supply, this additional exothermic reaction can be maintained over the entire guided flying time of the missile without the radiator being destroyed.

In a preferred arrangement of the invention, at least two concentric radiation tubes are arranged in the receiver as a radiation-emitting body. Due to this arrangement, an optimum radiation is achieved relative to the dimensions of the receiver, since a relatively wide and flat radiator surface is formed by the concentric arrangement of several tubes. In addition, the shadowing of the radiation originating from the back of the radiator and emanating from the reflector arrangement in the back wall of the receiver is less pronounced with two or more juxtaposed tubes than with a single tube with a corresponding larger cross-section. The arpressure coupling including a first coupling member upon the skid and a mating coupling member upon the rolling-mill stand and interengageable automatically upon the insertion of the skid and the working rolls carried hereby into the stand through the opening. The coupling may be of the male-female or plug-socket type and the mating members are axially aligned along an axis which is offset from but parallel to the axis of the rolls. Preferably, the skid is formed with a cross piece (between runners) which is engageable by the fluidresponsive feed assembly and is located at the ends of the working rolls remote from their drive extremities. The drive extremities of the working rolls may, of course, be receivable in drive sockets of any conventional configuration. It has also been found to be desirable to provide the gap-adjusting means with a facility to relieve the pressure upon the working rolls when the latter is to be withdrawn from the manner previously described. For the most part, best results are obtained when the hydraulic connection is automatic as the slide or skid is inserted, the connection being made at the driving side of the stand.

The system of the present invention and described briefly above, has numerous advantages aside from the fact that it enables the working rolls with the associated journal blocks and spacer arrangement to be removed rapidly from the rolling stand, to be inserted therein or to be replaced. Of greater significance is the reduction in the amount of manual labor which has hitherto been required for positioning, displacing and reconnecting the working rolls of a rolling mill for bands and the like.

DESCRIPTION OF THE DRAWING The above and other objects, features and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is a vertical cross section taken generally transversely to the rolling direction of a rolling mill diagrammatically illustrating the invention.

FIG. 2 is an elevational view, drawn to an enlarged scale, of the replaceable rolling-roll assembly;

FIG. 3 is a cross-sectional view taken along the line III III of FIG. 2; and

FIG. 4 is an elevational view ofa skid for use with the system of FIGS. 2 and 3.

SPECIFIC DESCRIPTION In FIG. I of the drawing there is shown a rolling mill, in part represented at l, which comprises the usual stand 1a within which back-up rolls lb and 1c are journaled in respective blocks 1d and 1e. The stand 1a is provided with an opening 1f adapted to permit insertion and removal of the working rolls 4 which fit into the gap lg between the take-up rolls lb and 1c. A platform 1h upon the stand la serves as a guide for the skid 7 12 carrying the working rolls into the installation. The means for driving the rolls are, of course, conventional and need not be described here.

The working rolls 4, as best seen in FIGS. 1 3, each comprise a rolling central portion 4a having chamfered ends 4b and cylindrical bearing portions 40 and 4d at opposite axial extremities of the roll. At one end, each of the rolls 4 may be formed with a fitting 4e having a noncircular tongue 4f receivable in a complementary socket of the drive means.

Each of the rolls 4 is, moreover, journaled in a block 3 serving to rotatably support the rolls relative to one another and to accommodate spacing means as well as the means for adjusting the rolling gap 4g. The rolls and installation illustrated in FIGS. 1 and 2 are those of a band or strip mill as already indicated.

As best seen in FIGS. 2 and 3, each of the lower journal blocks 3a is provided with a pair of cylinders 3b accommodating hydraulic plungers 30 which project into and are received within recesses 3d formed in the upper bearing block. When hydraulic fluid is introduced into the cylinders 3b below the plungers 30, therefore, the pairs of bearing blocks 3, 3a are urged apart.

As the rolls are inserted into the mill, the cylinders are pressurized to hold the rolls 4 apart. Since the workpiece forced through the gap 4g is thicker than the gap width, the compression of the workpiece will generate vertical forces which are transferred by the working rolls 4 to the respective back-up rolls lb and 10.

According to the principles of the present invention, alongside the rolling mill 1 and parallel to the direction of rolling (perpendicular to the plane of the paper in FIG. 1), there is provided a drive arrangement having one or more plates or platforms 2. The platforms 2 preferably constitute the upper surfaces of carriages 2a which may have a chassis 2b rotatably supporting wheels 2c received in a channel-shaped track 2d and upon a flat rolling surface 2e of a guideway 2f shown diagrammatically in FIG. 1. The means for shifting the carriages along this guideway is represented diagrammatically at 2g and may be an electric or fluid motor.

As is also apparent from FIG. 1, the upper surface 211 of the platform 2 is coplanar with the surface lb of the receiving table so that the working-roll assembly can be shifted into the installation I with ease.

In the vertical plane of the axes of the back-up rolls lb and 1c and, of course, of the working rolls 4 when they are in position, there is provided a pusher assembly generally represented at 5 for inserting and withdrawing the working rolls. To this end, the assembly 5 may comprise a piston-and-cylinder arrangement 5a of the telescoping type, the head 5b of which is provided with a downwardly open recess adapted to engage a hook-shaped formation 20 upon the skid as will be described in greater detail hereinafter. When the hydraulic cylinder arrangement 5a extends, therefore, it thrusts the working-roll assembly to the right (arrow A) through the opening 1 f in the stand la of the mill, and thereby positions the working rolls 4 in the latter. The head 5b is tilted upwardly to release the hook 20 and the cylinder is withdrawn. When it is desired to replace an existing set of working rolls, however, an empty platform 2 is positioned ahead of the opening 1 f, the cylinder 5a is extended to permit the head 5b to engage the hook 20 of the skid of the assembly, the cylinder 50 is retracted to withdraw the skid and the working rolls 4 carried thereby onto the platform 2, and the hook 20 is released. Prior to withdrawal of the working rolls, however, the cylinders 3b which are generically illustrated as spacer means at 14 in FIG. 2, are depressurized to bring the working rolls together and permit them to move out of the gap 1g between the back-up rolls with ease.

radiators which do not have the filter disc 42 and which undergo no relative movement with respect to the surrounding air. In such an open embodiment of pyrotechnic radiator, such as shown in FIG. 1, air slots 75, arranged on a surface of an exterior wall of the housing and admitted with an air current, also effect an exactly dosed oxygen supply to the radiation tube or tubes so that they undergo an optimum oxidation during the combustion of the pyrotechnic substance contained therein. But if such an open radiator moves relative to the surrounding air, for example, if it is arranged on a high-speed missile such as the missile 7, then the open end face which is exposed to air current must be reduced in such a radiator so that it receives only a smaller dosed amount of oxygen. In such a case, the amount of oxygen arriving in the open radiator connected with the missile is throttled. This can be effected, for example, by covering the open radiator from the air current and by providing only a few slots with a supply of doses of oxygen.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A pyrotechnic radiator, particularly for the infrared location of automatically moving bodies and which is operable in the infrared spectral region, comprising a radiation-emitting body and an energy source heating said body, said emitting body comprising at least one thin-walled tube of any cross-section, a housing enclosing at least a portion of said tube, and means for supplying oxygen from the exterior of said housing into said housing adjacent said tube in order to provide optimum radiation yield of said tube, said tube being filled with a pyrotechnic incandescent composition giving off heat energy without any exterior flame and a marked evolution of gas and comprising said energy source for heating said body.

2. A pyrotechnic radiator, according to claim 1, wherein said tube is made of tantalum.

3. A pyrotechnic radiator package, comprising a housing having a radiation-emitting side with a radiation window, a radiation-emitting tube in said housing, said tube having a pyrotechnic incandescent composition therein which gives off heat energy without any exterior flame and marked evolution of gas when it is ignited, ignition means carried on said housing for igniting the pyrotechnic incandescent composition, said housing having at least one opening therethrough providing a passage for air to provide a turbulent flow of oxygen at the interior of said housing during operation of said emitter to maintain an optimum radiation yield thereof.

4. A pyrotechnic radiator package, according to claim 3, wherein said housing is at least partially annular, said emitting window being provided with a filter for controlling the optical radiation and substantially closing this end.

5. A pyrotechnic radiator package, according to claim 3, wherein said housing is trough-shaped and includes a trailing end having the radiation-emitting window, said window being closed by a filter for regulating the optical characteristics of the radiation.

6. A pyrotechnic radiator package, according to claim 3, wherein there are at least two emitter tubes within said housing arranged concentrically one within the other.

7. A pyrotechnic radiator, particularly for the infrared location of automatically moving bodies and which is operable in the infrared spectral region, comprising a radiation-emitting body and an energy source heating said body, said emitting body comprising at least one thin-walled tube of any cross-section, a housing enclosing at least a portion of said tube, and means for supplying oxygen from the exterior of said housing into said housing adjacent said tube in order to provide optimum radiation yield of said tube, said tube'being filled with a pyrotechnic incandescent composition giving off heat energy without any exterior flame and a marked evolution of gas and comprising said energy source for heating said body, said housing including a plurality of slots comprising said means for supplying oxygen and extending over one exterior surface for admitting an air current therethrough into said housing, said slots being of a number and size to provide for a turbulent air flow in controlled amounts to the interior of said housing.

8. A pyrotechnic radiator, particularly for the infrared location of automatically moving bodies and which is operable in the infrared spectral region, comprising a radiation-emitting body and an energy source heating said body, said radiation-emitting body comprising at least two concentric tubes of any cross-section, a housing enclosing at least a portion of said tubes, and means for supplying oxygen from the exterior of said housing into said housing adjacent said tubes in order to provide optimum ignition and radiation yield of said tubes, said tubes being filled with a pyrotechnic incandescent composition giving off heat energy without a marked evolution of gas and comprising said energy source for heating said body.

9. A pyrotechnic radiator package, comprising a housing having a radiation-emitting side with a radiation window, a radiation-emitting tube in said housing, said tube having a pyrotechnic incandescent composition therein which gives off heat energy without marked evolution of gas when it is ignited, ignition means carried on said housing for igniting the pyrotechnic incandescent composition, said housing having at least one opening therethrough providing a passage for air to provide a turbulent flow of oxygen at the interior of said housing during operation of said emitter to maintain an optimum radiation yield thereof, said housing being at least partially annular, said emitting window being provided with a filter for controlling the optical radiation and substantially closing this end, and a plurality of slots defined in a wall of said housing providing said means for supplying air for oxygen to the interior of said housing.

10. A pyrotechnic radiator package, comprising a housing having a radiation-emitting side with a radiation window, a radiation-emitting tube in said housing, said tube having a pyrotechnic incandescent composition therein which gives off heat energy without 'marked evolution of gas when it is ignited, ignition means carried on said housing for igniting the pyrotechnic incandescent composition, said housing having at least one opening therethrough providing a characteristics of the radiation and being of annular configuration and including an inner circumference having a plurality of slots therein constituting said means for directing air into the interior of said housing. 

2. A pyrotechnic radiator, according to claim 1, wherein said tube is made of tantalum.
 3. A pyrotechnic radiator package, comprising a housing having a radiation-emitting side with a radiation window, a radiation-emitting tube in said housing, said tube having a pyrotechnic incandescent composition therein which gives off heat energy without any exterior flame and marked evolution of gas when it is ignited, ignition means carried on said housing for igniting the pyrotechnic incandescent composition, said housing having at least one opening therethrough providing a passage for air to provide a turbulent flow of oxygen at the interior of said housing during operation of said emitter to maintain an optimum radiation yield thereof.
 4. A pyrotechnic radiator package, according to claim 3, wherein said housing is at least partially annular, said emitting window being provided with a filter for controlling the optical radiation and substantially closing this end.
 5. A pyrotechnic radiator package, according to claim 3, wherein said housing is trough-shaped and includes a trailing end having the radiation-emitting window, said window being closed by a filter for regulating the optical characteristics of the radiation.
 6. A pyrotechnic radiator package, according to claim 3, wherein there are at least two emitter tubes within said housing arranged concentrically one within the other.
 7. A pyrotechnic radiator, particularly for the infrared location of automatically moving bodies and which is operable in the infrared spectral region, comprising a radiation-emitting body and an energy source heating said body, said emitting body comprising at least one thin-walled tube of any cross-section, a housing enclosing at least a portion of said tube, and means for supplying oxygen from the exterior of said housing into said housing adjacent said tube in order to provide optimum radiation yield of said tube, said tube being filled with a pyrotechnic incandescent composition giving off heat energy without any exterior flame and a marked evolution of gas and comprising said energy source for heating said body, said housing including a plurality of slots comprising said means for supplying oxygen and extending over one exterior surface for admitting an air current therethrough into said housing, said slots being of a number and size to provide for a turbulent air flow in controlled amounts to the interior of said housing.
 8. A pyrotechnic radiator, particularly for the infrared location of automatically moving bodies and which is operable in the infrared spectral region, comprising a radiation-emitting body and an energy source heating said body, said radiation-emitting body comprising at least two concentric tubes of any cross-section, a housing enclosing at least a portion of said tubes, and means for supplying oxygen from the exterior of said housing into said housing adjacent said tubes in order to provide optimum ignition and radiation yield of said tubes, said tubes being filled with a pyrotechnic incandescent composition giving off heat energy without a marked evolution of gas and comprising said energy source for heating said body.
 9. A pyrotechnic radiator package, comprising a housing having a radiation-emitting side with a radiation window, a radiation-emitting tube in said housing, said tube having a pyrotechnic incandescent composition therein which gives off heat energy without marked evolution of gas when it is ignited, ignition means carried on said housing for igniting the pyrotechnic incandescent composition, said housing having at least one opening therethrough providing a passage for air to provide a turbulent flow of oxygen at the interior of said housing during operation of said emitter to maintain an optimum radiation yield thereof, said housing being at least partially annular, said emitting window being provided with a filter for controlling the optical radiation and substantially closing this end, and a plurality of slots defined in a wall of said housing providing said means for supplying air for oxygen to the interior of said housing.
 10. A pyrotechnic radiator package, comprising a housing having a radiation-emitting side with a radiation window, a radiation-emitting tube in said housing, said tube having a pyrotechnic incandescent composition therein which gives off heat energy without marked evolution of gas when it is ignited, ignition means carried on said housing for igniting the pyrotechnic incandescent composition, said housing having at least one opening therethrough providing a passage for air to provide a turbulent flow of oxygen at the interior of said housing during operation of said emitter to maintain an optimum radiation yield thereof, said housing being trough-shaped and includes a trailing end having the radiation-emitting window, said window being closed by a filter for regulating the optical characteristics of the radiation and being of annular configuration and including an inner circumference having a plurality of slots therein constituting said means for directing air into the interior of said housing. 